title: Unprecedented alkylzinc-magnesium alkoxide clusters as suitable organometallic precursors for magnesium-containing ZnO nanoparticles.
abstract: The synthesis and characterization of the first heterobimetallic methylzinc-magnesium alkoxide clusters [Me(6)MgZn(6)(OR)(8)] [R=Et (1 a), n-Pr (1 b), nBu (1 c)] with a bis-cubane-shaped MgZn(6)O(8) core is described. The thermal degradation of 1 a-c and mixtures of 1 a and the homometallic MeZn-alkoxide cubane [{MeZnOtBu}(4)] (2) in dry synthetic air led to wide-band-gap semiconducting Mg(x)Zn(1-x)O nanoparticles at temperatures below 500 °C. The final materials were characterized by different analytical techniques such as PXRD, REM, TEM, EDX, and IR spectroscopy. The morphology of the as-prepared magnesium-containing ZnO samples is influenced by the different organo groups (alkoxo) in the precursors. EDX mapping showed that magnesium is uniformly distributed in the ZnO matrix. The incorporation of magnesium led to a distortion of the ZnO lattice with increased a axis and decreased c axis parameters. Room-temperature photoluminescence (PL) spectra reveal that the near-band-edge (NBE) emission of Mg(2+)-doped ZnO is shifted to higher energies relative to that of pure ZnO.
authors.affiliation: Institute of Chemistry: Metalorganics and Inorganic Materials, Technische Universität Berlin, Berlin, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Heitz
authors.forename: Yilmaz
authors.initials: Y
authors.lastname: Aksu
authors.forename: Christoph
authors.initials: C
authors.lastname: Merschjann
authors.forename: Matthias
authors.initials: M
authors.lastname: Driess